The invention relates generally to internal combustion engines and, more particularly, to fuel injected internal combustion engines. Still more particularly, the invention relates to fuel injected engines in which the fuel is conveyed to the combustion chambers by a relatively low pressure gas, such as air.
Still more particularly, it has been recognized that direct cylinder fuel injection can be employed to reduce or eliminate short circuiting of air/fuel mixture out of a two-stroke exhaust port with resulting improvement in engine efficiency and a reduction in exhaust emissions.
The concept of using pressurized air as a means of atomizing relatively low pressure fuel has been employed effectively to improve the efficiency of such internal combustion engines while using a relatively low cost fuel system.
In order to utilize this concept, a supply of pressurized air is required. Such pressurized air has commonly been supplied by a mechanically or electrically driven air compressor. Such systems work efficiently but the need to provide a compressor imposes additional mechanical complexities and cost disadvantages on the otherwise relatively low cost fuel system.
Attention is directed to the following U.S. Patents:
______________________________________ U.S. Pat. Nos. ______________________________________ 681,111 E. N. Dickerson August 20, 1901 1,013,528 J. K. Broderick January 2, 1912 1,015,817 L. L. McLarty January 30, 1912 1,060,820 H. E. Coffin May 6, 1913 1,087,857 R. E. Wetzel February 17, 1914 1,098,047 D. D. Miles, Jr. May 26, 1914 1,211,231 H. E. A. Raabe January 3, 1917 1,230,536 C. L. Stoeltzlen June 19, 1917 1,551,731 J. A. Charter January 29, 1923 4,462,760 T. R. Sarich, et al. July 31, 1984 4,554,945 M. L. McKay November 26, 1985 ______________________________________